WASHINGTON – Sen. Ted Cruz was confronted at Los Angeles International Airport on Sunday by protesters who decried the detention of migrants at the U.S.-Mexico border.

A video shared on social media showed people in the airport chanting, "Free the children!" as a smiling Cruz stood uncomfortably in the terminal.

"Americans will not be silenced!" at least one protester shouted.

At one point, the Texas Republican took time to pose for a photograph with a woman even as the chants continued.

The Twitter account for AFSCME Local 3299, a union representing employees of the University of California system, said members of the union's Immigration Committee spotted Cruz at the airport and confronted him "about the inhumane conditions" at Immigration and Customs Enforcement detentions centers in Texas.

Sen. @TedCruz was encountered by fans and non-fans at LAX over the weekend with a group chanting "Free the children!"

"I'm sorry, we're trying to catch a flight," Cruz, who was heading to Houston, told the committee members as they introduced themselves.

"Free the children!" they chanted as he walked away while continuing to speak with one of the union representatives who had introduced herself. They appeared to follow Cruz to his gate, where they continued to chant.

San Francisco Board of Supervisors member Hillary Ronen said on Facebook that she was getting off a plane when she saw the union activists confronting Cruz. She decided she would also share her feelings on the immigration debate with Cruz.

"Although many may say it’s pointless, I will never miss an opportunity to confront those in power and appeal to their conscience. And we must not let them have any peace until there is justice," Ronen said of her decision to confront Cruz.

"I represent the biggest Latino community in the district and we are horrified by what is happening with the caging of children and the separation of families," she told Cruz. "I don't know how you can live with yourself supporting these policies."

"Ma'am, the cages were built by President Obama," Cruz said.

"Kids are dying and families are being separated, and it's disgusting," she told Cruz. "Please do something to stop it. You have a power."

"I have been leading the fight to stop this," Cruz said. But he blamed "Democratic filibusters" for "stopping efforts to close the loopholes."

Cruz again told Ronen that the "cages" were built during the Obama administration.

"I don't care who built them, dismantle them," she said.

"So you want to just leave children in street?" he asked Ronen, who said she did not but wished to see them reunited with their families or placed in foster care if that was not possible.

Cruz argued that under current policies, "We are incentivizing human traffickers and drug traffickers to take children into this country." He said DNA testing conducted in the Rio Grande Sector showed that nearly 30% of the cases showed no biological connection between the children and the people they were traveling with, repeating a figure he cited during an address from the Senate floor earlier this month.

In May, the Department of Homeland Security launched a pilot program to test the DNA of migrant families to determine whether they had a biological connection as part of an effort to weed out those who might be trying to get favorable treatment in asylum cases.

Cruz said he was told the 30% figure by Border Patrol officials during a visit to the Rio Grande Valley.

In his testimony before the House Oversight Committee this month, Acting Homeland Security Secretary Kevin McAleenan echoed Cruz's concerns about what he called "child recycling," or "adults that are bringing children with them who are not their own."

But McAleenan said Homeland Security investigators found there was no familial connection in about 15% cases. And that was in cases that had been flagged by Border Patrol agents because they had concerns.

According to ICE data provided to USA TODAY, between mid-April and July 19, there were 3,002 migrant families interviewed where potential fraud had been identified. In 13% of those cases, fraud was found, with as many as 682 people facing prosecution, ICE said.

During his conversation with Ronen, at least two supporters interrupted to express their support for the senator.

At that point, a Cruz supporter interrupted to tell the senator, "Praise God, Ted. We approve 100%, We support you 110%."

Cruz speaks with commentator Mark Levin during a discussion of the Constitution during the Conservative Political Action Conference at National Harbor, Md., on Feb. 23, 2017. Mike Theiler, AFP/Getty Images

Cruz tops to answer a question from members of the media following a news conference with Texas Gov. Greg Abbott, about the resettlement of Syrian refugees in the U.S., during a news conference on Capitol Hill on Dec. 8, 2015. AP

Cruz speaks at a rally in front of the World War II Memorial on Oct. 13, 2013, in Washington as Senate leaders search for a deal to end the partial government shutdown and avert a federal default. Alex Brandon, AP

Ted Cruz, then the Texas solicitor general, and Don R. Willett, then the deputy state attorney general for legal counsel, leave the federal courthouse after a pre-trial hearing on Dec. 9, 2003, in Austin. Harry Cabluck, AP